Hi cyteen, sorry to hear about this problem.

When did the problem start? For example, during the initial installation of Firefox 67 on or after May 21, 2019. Or earlier?

Did you notice any other problems in Firefox at that time, such as extensions getting removed, missing settings, etc.?

Is there evidence that your Firefox performed a Refresh: that would move your data folder to your desktop inside an "Old Firefox Data" folder. Do you see anything like that?

After May 21. I did have to redo a few settings on a previous update; on this last update I had to enable the extensions I have. No folder.

Thinking back, when I redid a few settings, I may have cleared the cache; would that have cleared the OneTab listing as well?

Using the internal cache cleaning shouldn't affect extension data.

I'll mention one other recent thing that is affecting several users:

Firefox 67 Profile Migration Issue

Firefox 67 made some changes to how profiles work, and for some users, there is a glitch in the migration. So with that possibility in mind:

If you haven't already, could you close out of Firefox and do a normal Windows shutdown and restart to complete any pending updates and release any file locks.

If Firefox again starts up without your regular data, could you check whether your stuff is available in a different profile, as follows:

Profile Manager Page

Inside Firefox, type or paste about:profiles in the address bar and press Enter/Return to load it.

This page should list at least one profile and could list many. Each will show links to a pair of folders; please ignore those for now. Please do not use any Remove buttons!

The profile that Firefox is currently using will have this:

This is the profile in use and it cannot be deleted.

Do you have another profile named default or default-longnumber listed on this page? If so, you can check whether it is the one you were using recently by clicking its Launch profile in new browser button.

If it isn't what you want, simply close that new window.

If it IS what you want, back on the about:profiles page, click the Set as default profile button for that profile so Firefox uses it automatically at the next startup.

Any progress so far?

Firefox and Windows had both been closed and restarted before I asked my question. There was another profile and I picked up a few OneTab items that had been lost, but it did not include the larger number that I had lost previously.

What kind of data was the OneTab extension storing?

If it was keeping track of open tabs, you might be able to extract those from one of Firefox's session history files. Firefox doesn't retain very many closed tabs, however.

Back up and inspect session history files

Firefox creates numerous session history files, but because session history is only for the immediately previous session, it is unfortunately too easy to lose it. Could you start by making a backup of your existing session history files? Here's how:

You can open your current Firefox settings (AKA Firefox profile) folder using either

• "3-bar" menu button > "?" Help > Troubleshooting Information
• (menu bar) Help > Troubleshooting Information
• type or paste about:support in the address bar and press Enter

In the first table on the page, click the "Open Folder" button.

In your profile folder, double-click into the sessionstore-backups folder. Save all files here to a safe location such as your Documents folder.

The kinds of files you may find among your sessionstore files are:

• recovery.jsonlz4: the windows and tabs in your currently live Firefox session (or, if Firefox crashed at the last shutdown and is still closed, your last session)
• recovery.baklz4: a backup copy of recovery.jsonlz4
• previous.jsonlz4: the windows and tabs in your last Firefox session
• upgrade.jsonlz4-build_id: the windows and tabs in the Firefox session that was live at the time of your last update
• some older .js files from Firefox 55 or earlier

Could you take a look at what you have and the date/time of the various files to see whether you think any of them would have the missing tabs?

To preview the contents of a file, you can drag and drop it onto this page, then click Scrounge URLs: https://www.jeffersonscher.com/ffu/scrounger.html

That tool is on my site, so please let me know if it doesn't work for you.

Interesting. When I went to save those files somewhere else, I found an "Old Firefox Data" folder from Sept 2018. I'm playing around with putting different files on your page. So far, I don't think I've found the actual OneTab items as a group, but I have found various URL's that I may have had on it. There is a folder in the "Old Data" folder that in one of it's sub-folders has a .sqlite file that has something to do with OneTab. As far as I know I don't have anything to read .sqlite, so I'm not sure what might be in it.

One thing is for sure, anytime I let Firefox update, I'm exporting whatever I have in OneTab, maybe even bookmarks, and passwords. I was just looking at passwords and I see "Import" but not "export"?

Oh, and looking at one of the extracted URL's page, I see OneTab listed (moz-extension://36abea0d-069a-40b5-a4e1-b75414020b47/onetab.html). When I click it, it comes as a blank page.

cyteen said

I'm playing around with putting different files on your page. So far, I don't think I've found the actual OneTab items as a group, but I have found various URL's that I may have had on it.

Those are Firefox's own session history files, not OneTab files, so there won't be a perfect correspondence.

There is a folder in the "Old Data" folder that in one of it's sub-folders has a .sqlite file that has something to do with OneTab. As far as I know I don't have anything to read .sqlite, so I'm not sure what might be in it.

Currently, extension data is stored in IndexedDB databases. You can find them under

[profile]\storage\default\moz-extension......\idb\

However, the data in these files is difficult to extract in a readable format.

Previously, OneTab extension data was stored under

[profile]\browser-extension-data\extension@one-tab.com

in a file named storage.js

At some point, that would have been migrated into an IndexedDB database, with the old file renamed to

storage.js.migrated

You could "Scrounge" that file to see what it contains.

One thing is for sure, anytime I let Firefox update, I'm exporting whatever I have in OneTab, maybe even bookmarks, and passwords. I was just looking at passwords and I see "Import" but not "export"?

You can back up critical files from time to time: Back up and restore information in Firefox profiles.

cyteen said

Oh, and looking at one of the extracted URL's page, I see OneTab listed (moz-extension://36abea0d-069a-40b5-a4e1-b75414020b47/onetab.html). When I click it, it comes as a blank page.

I suspect that is a page the extension displays, and not your data.

"Currently, extension data is stored in IndexedDB databases. You can find them under

[profile]\storage\default\moz-extension......\idb\"

That's where I found a .sqlite file.

"[profile]\browser-extension-data\extension@one-tab.com

in a file named storage.js"

I found some things there. I'm not sure it's everything I thought I had, maybe I lost it further back and didn't realize it.

Thank you very much for your help.

Note that it is possible to remigrate data from browser-extension-data to indexedDB (storage/default).

What you can do to re-migrate the data:

• https://www.ghacks.net/2018/08/06/dont-downgrade-firefox-63/

Keep a backup copy of storage.js.migrated.

1. uninstall extension
2. close Firefox
3. browser-extension-data\<extension-id>\storage.js.migrated => storage.js
4. delete compatibility.ini
5. restart Firefox
6. reinstall extension

My computer crashed yesterday and when it came back up OneTab was blank. I'm going to recover what I can from the above suggestions and save as bookmarks; I can organize them in folders then.